There is continuing interest to improve testing methodologies and decrease time demands on clinical laboratories. Particular testing requires that a sample be broken down to extract nucleic acid molecules such as DNA or RNA.
It is estimated that about 30 million molecular diagnostic tests took place in US medical facilities in 2007. This figure is expected to increase to 67 million in 2009. Many, if not all of these assays, could benefit from a rapid sample preparation process that is easy to use, requires no operator intervention, is cost effective and is sensitive to small size samples.
The use of molecular diagnostics and gene sequencing in research and medical diagnostics are rapidly growing. Molecular techniques provide higher levels of specificity and sensitivity than antibody methods, Genetic sequencing allows for the collection of larges amounts of information not previously available. However, sample preparation is a major cost component of running PCR, real-time PCR, gene sequencing analysis and hybridization testing. In addition, it delays test results and limits the ability to run these assays to laboratories with well trained personnel.
Nucleic acid based identification of biological material first requires isolation of the nucleic acid molecules (NAMs) from the sample. In order for a system to effectively and efficiently meet the users needs, a universal sample preparation process is required. Current sample preparation processes are laborious, time consuming and require laboratory capability. To remain universal, the process must be able to handle a wide variety of input materials. This includes, but is not limited to, viruses, spores, organisms, bacteria and medical diagnostic materials, such as blood, tissue, saliva, urine and feces.
Bead beating has been used for years to isolate nucleic acid molecules from samples. Bead beating is the agitation, usually by ultrasound, of micron size glass beads added to the sample. It is a robust approach which is well suited for use with solids like spores or tissue.
Bead beating has several drawbacks. On one hand, if the sample is treated too long, or at too high a power level, only short fragments less than 100 bases long are produced. On the other hand, if the sample is treated to brief, low power agitation, a low yield of nucleic acid is produced, along with a wide range of fragment sizes. When particular size ranges of nucleic acids are needed, gel electrophoresis of the sample is sometimes employed, cutting the gel sections with the correct size ranges out of the finished gel and extracting the nucleic acid fragments from the gel. This process is both slow and tedious.
In running biological and chemical tests it is often desired to obtain a usable size range of nucleic acid molecules and to concentrate and retain the desired analyte. Concentrating the sample can be a difficult process. Traditional methods for concentrating a biological sample include filtering, rinsing, centrifuging and/or reaction chemistry. Often these steps cannot be preformed in a single processing chamber and require the sample to be transferred to other devices or chambers.
Magnetic nanoparticles are particles which are attracted to a magnetic field. By attaching a magnetic nanoparticle to nucleic acid polymers and applying a magnetic field to a sample, the nucleic acid polymers can be moved to a desired location, thereby concentrating a portion of the sample with the nucleic acid polymers. The sample can then be drawn from the concentrated portion yielding a high amount of nucleic acid polymers.
Appling a magnetic field further allows for manipulating the nucleic acid polymer. For example, by holding a nucleic acid polymer steady a rinse can be applied without washing away the nucleic acid polymer.
In an array of different sensors applying a magnetic field allows for positioning the nucleic acid polymer in the vicinity of a desired test area. The nucleic acid polymer can be manipulated to sequentially interact with a plurality of test areas.
Fluid analysis generally requires a series of process steps. Theses process steps generally require that distinct fluids contact a reaction area at different times and in varying secession. Furthermore, each fluid may require different pre-treatment prior to contacting the reaction area such as chemical, optical, thermal, mechanical, magnetic or acoustical pre-treatment steps. A single fluid sample may be subjected to a variety of pre-treatment steps prior to contact with a reaction area such as heating or ultrasonic processing. As the number of fluids and pre-treatment steps increase the fluid delivery system becomes more complex.
Present designs for fluid delivery systems are customized for a particular process and are not easily converted to new processes. Generally, fluid delivery systems comprise a series of chambers uniquely configured for pre-treating and delivering a particular fluid. These systems are not easily adaptable to new pre-treatment steps or fluid delivery without changing both the chambers and delivery procedure.
Therefore, there is a need for a method to prepare nucleic acid samples from any source in a desired size range, rapidly and economically.
Further, a magnetic entanglement particle that specifically binds to target analytes is desired.
Even further, an entanglement particle having magnetic properties is desired.
Therefore, there is a need for a fluid delivery system that is easily configurable to new delivery procedure and pre-treatment steps.
Further, there is a need for a disposable fluid delivery system that can be easily inserted and removed from a bench-top or portable device.
Yet further, there is a need for a fluid delivery system that is easily manufactured and customizable to suit varying fluid delivery needs.